Many vehicles, in particular, motor vehicles, are provided with a steering wheel that acts upon the wheels (or a rudder, respectively) via a steering column and consequently makes it possible to steer the vehicle. In addition, a so-called steering column switch is usually arranged within the region of the steering column. The housing of the steering column switch is arranged stationary with respect to the vehicle housing. Such a steering column switch serves for actuating various electrically operated devices, e.g., the windshield wiper, the windshield washer, the lights, etc.
In addition, a contact is arranged on the rotatable steering wheel in order to provide easy access to a contact that triggers an acoustic warning device (e.g., the horn). This contact is connected to the warning device via the housing of the steering column switch. Since the electric connection between the warning contact and the housing of the steering column switch needs to be ensured over the entire service life of the vehicle, the connection between the warning contact and the housing of the steering column switch is realized by means of a so-called spiral spring. This particular measure also applies to the electric line that serves for triggering the airbag.
The spiral spring represents a cylindrical, coiled connecting line, one end of which is rigidly anchored to the housing of the steering column switch and the other end of which is connected to the rotatable warning contact, the airbag or another electrical device arranged on the steering wheel. Since the rotational movement of the warning contact is largely distributed over the individual windings of the spiral spring during the steering process, the relative movement of the individual sections of the spiral spring is comparatively small, i.e., the connecting wires are only subject to slight wear during the long service life of the vehicle.
One disadvantage of known spiral springs is that they are supplied by a special manufacturer in a separate housing, i.e., the spring housing must be connected (e.g., locked in place) to the housing of the steering column switch during the assembly of the vehicle.